percentile_cont in js

percentile_cont.js

// http://stackoverflow.com/questions/14300004/postgresql-equivalent-of-oracles-percentile-cont-function
var percentile_cont = function (data, percentile) {
    var row = (percentile*(data.length -1));
    var crn = Math.ceil(row);
    var frn = Math.floor(row);
    var result = 0.0;

    data.sort(function(a,b){return a-b});

    if ((crn == frn) && (frn == row)) {
        result = data[row];
    } else {
        result = (crn - row) * data[frn] + (row - frn) * data[crn];
    }
    return result;
};

var example = [5.1345, 195.1345, 1095.1345,
    5995.1345, 15.1345, 25.1345, 495.1345,
    35.1345, 695.1345, 595.1345, 35.1345,
    30195.1345, 165.1345, 65.1345, 955.1345,
    135.1345, 19195.1345,
    145.1345, 85.1345, 455.1345];

percentile_cont(example, 0.25);